Several months ago I replaced two older toilets with low water-flow ones. One of the two works beautifully. The second one kept leaking water in 3-4 places around the top, right under the rim--just minute little seeps. After being unable to fix the problem, my plumber replaced the toilet. It's an American Standard, and now there's a new problem. This one leaks water into the bowl from the tank. It started out very slowly. I noticed a "water running through a pipe" noise that lasted for only 4 seconds or so and I finally figured out it was related to the toilet, especially when I noticed there was much more water in the bowl than at first. It seemed to be about 2/3 the amount of a regular toilet. My plumber made two calls and did the following: First call: "Replaced stem on Lav faucet. Adjusted toilets, water line may be loose in wall for toilet, found that toilet needed adjusting." Everything was fine for about two weeks, then it started in again. Second call, 2 weeks after first: "Checked all toilets in house. Tried to make toilet in master bath leak. Checked the fill hose and pulled out the restrictor to it and then reinstalled to see if anythng would leak. Nothing happened. Wouldn't leak." It was fine for a while, and then it started up again. Again, the leaking would go on for about 4 seconds. It's worked its way up to leaking for about 15 seconds at a time. I can see the water slowly rising in the bowl, kind of bulging up the sides, and then everything stops. The leaking is utterly random. I'm at work during the day but hear the "water running through a pipe" noise maybe 2-4 times in the evening. My plumber is baffled. I'm frustrated. We both need help, please. Thank you. P.S. I'm on a septic system and went low-flow toilets to go easy on the system. Double help!!